45 research outputs found
Action of Pyrroloquinolinequinol As an Antioxidant Against Lipid Peroxidation in Solution
This is the publisher's version, also available electronically from: http://online.liebertpub.com/doi/pdfplus/10.1089/ars.1999.1.4-547.The activities of pyrroloquinoline quinone (PQQ), a coenzyme of methanol dehydrogenase and amine oxidase,
and its reduced form pyrroloquinoline quinol (PQQH2 ) as an antioxidant have been measured in solution. PQQH2
was stable in the absence of oxygen but rapidly auto-oxidized to PQQ in the presence of oxygen in water. PQQH2
was stable in an aprotic solvent such as acetonitrile, even in air. PQQ did not exert appreciable antioxidant activity,
whereas PQQH2 exerted higher reactivity than a-tocopherol toward galvinoxyl radical and peroxyl radical.
PQQH2 acted as a potent antioxidant against the oxidation of methyl linoleate in acetonitrile induced by azo compound
and produced a clear induction period, from which the apparent stoichiometric number was obtained as
1.1. PQQH2 reduced the a-tocopheroxyl radical and spared a-tocopherol in the oxidation of methyl linoleate. These
results suggest that PQQH2 may act as a potent antioxidant, particularly in combination with a-tocopherol. Antiox.
Redox Signal. 1, 547-554
Giant gastrointestinal stromal tumor, associated with esophageal hiatus hernia
An 85-year-old woman was admitted to our hospital because of vomiting. An upper gastrointestinal series what showed a large esophageal hiatus hernia, suggesting an association with extrinsic pressure in the middle portion of the stomach. An upper gastrointestinal endoscopic examination showed severe esophagitis and a prominent narrowing in the middle portion of the stomach, however, it showed normal gastric mucosa findings. CT and MRI revealed a large tumor extending from the region of the lower chest to the upper abdomen. From these findings, the tumor was diagnosed as gastrointestinal stromal tumor(GIST), which arose from the gastric wall and complicated with an esophageal hiatus hernia. We performed a laparotomy, however, the tumor showed severe invasion to the circumferential organs. Therefore, we abandoned the excision of the tumor. Histologically, the tumor was composed of spindle shaped cells with marked nuclear atypia and prominent mitosis. The tumor cells were strongly positive for CD34 and c-kit by immunohistochemical examination. From these findings, the tumor was definitely diagnosed as a malignant GIST. As palliative treatment, we implanted a self-expandable metallic stent in the narrow segment of the stomach. The patient could eat solid food and was discharged. In the treatment of esophageal hiatus hernia, the rare association of GIST should be considered